1. Field of the Invention
The present invention is directed to eyeglasses which are used intermittently. Examples of eyeglasses for intermittent use include bifocal glasses, sunglasses and reading glasses (magnifiers). More particularly the invention relates to sunglasses which are easy to carry and which have lenses which move into and out of the line of sight of the wearer.
2. Background Art
It is desirable that eyeglasses for intermittent use have lenses that are easily and quickly moveable into and out of the line of sight. In addition such glasses should fold as flat as possible so they may fit in a pocket without unnecessary discomfort.
Flip up eyeglasses and spectacles are known in the art. For example, U.S. Pat. No. 3,990,788 (Choy) discloses spectacles which contain a rotatable shaft and pivotable lens frames. By engaging a knob at the end of the glasses, the shaft is rotated and the lenses pivot out of the line of sight. U.S. Pat. No. 2,582,554 (Mendelsohn) relates to sunglasses, the lenses of which are swingingly mounted to move into and out of the line of sight of the wearer. U.S. Pat. No. 4,154,513 (Goulden) discloses sunglasses wherein the right and left lens are independently adjustable horizontally or vertically. U.S. Pat. No. 4,400,067 (Joffe) discloses 3D glasses, the lenses of which are rotatable into and out of the line of sight of the wearer. Compact folding glasses are also known in the art for example, U.S. Pat. No. 4,560,258. (Stanley).